Improved spike



UNlTED STATES PATENT @Ferca DANIEL R. PRATT, OF W'ORMESLIR7 MASSAGE USETTS, ASSIGNOR TU J. l\l.\'lt(1l 'S RGE, OF SAME PLACE.

llVIPROVEDSPiKE-I.

Speeilieution forming partof Letters Patent No. 5l .265; (lated November 25, 1865.

To all whom fit may concern:

Be it known that I, DANEL R. PRATT, of Worcester, in the county of Worcester and State ot Massachusetts, have invented a new and improved Spike and Nail for Fastening food Iand Metals Together for Railroads and other Purposes; and I do hereby declare that the following is a t'nll and exact description thereof', reference bei ng had to the accompanying models and drawings, and to the letters ot' reference marked thereon.

The nature ot' my invention consists in co-ry rugating the surfaces of the spikes or nails in such a manner as not to interfere with their being driven into the woodin the usual way nor prevent their being drawn without too much diiiiculty, as the surfaces are-elliptic in both directioi1st1"oni head to point and from point to head, of easy wave-shaped eorrugations7 and in such a 4m anner as not to infringe upon the thickness and strength of the body of the nail or spike.

The advantages of this useful invention are first, to prevent their heingjarred outot' their places when the timber is exposed to high at mospheric heat, as in the hot sun on a tie in the bed of a railwa7 in midsnnimcr,l thesun causing the timber to shrink awa-y from the spike or nail and the jarring motion'oi' the train passing over the track will canse the-spikes to risel outot' their places wh en the surfaces are smooth,

as in the old forms ot' spikes and nails, or as 

